Silver halide photographic emulsion for recording electron beam

ABSTRACT

WHEREIN Z is an atomic group required for forming a heterocyclic ring, R1 and R2 are lower alkyl group, L is a methine group, and n is 1 or 2.   The invention relates to a photographic emulsion for recording an electron beam which comprises fine grains of silver halide having adsorbed thereon at least one aminostyryl base represented by the following general formula:

' United States Patent [191 Nakazawa et al.

1 SILVER HALIDE PHOTOGRAPHIC EMULSION FOR RECORDING ELECTRON BEAM [75] Inventors: Yoshiyuki Nakazawa; Yashuharu Nakamura; Yosuke Nakajima; Junichi Matsuyama; Akira Sato, all of Minami-ashigara, Japan [73] Assignee: Fuji Photo Film Co., Ltd.,

Minami-ashigara, Japan [22] Filed: Nov. 5, 1973 [21] Appl. No.: 413,146.

Related US. Application Data [62] Division of Ser. No. 181,136, Sept. 16, 1971,

' abandoned.

[30] Foreign Application Priority Data 1 Dec. 23, 1975 OTHER PUBLICATIONS Herz, The Photographic Action of Ionizing Radiations, pp. 59-61, Wiley-Interscience, New York, 1969.

Primary Examiner- J. Travis Brown Attorney, Agent, or Firm-Sughrue, Rothwell, Mion, Zinn & Macpeak f I ABSTRACT The invention relates to a photographic emulsion for recording an electron beam which comprises fine grains of silver, halide having adsorbed thereon at least one aminostyryl base represented by the following general formula:

wherein Z is an atomic group required for forming a heterocyclic ring J2 and R are lower alkyl group, L is a rnethine group, and n is l or 2.

- 6Claims, No Drawings SILVER HALIDE PIIOTOGRAPIIIC EMULSION FOR RECORDING ELECTRON BEAM This is a division of application Ser. No. l8l,l36, filed Sept. 16, 1971, now abandoned.

I The present inventors have found a method for ele- BACKGROUND OF THE INVENTION vating remarkably the electron beam sensitivity of the II Field of the Invention 1 silver halide emulsion by adding an aminostyryl base to This invention relates to -a silver halide'photographic l9 i g iig Ielmulslon conmmmg tme purtlcles 0t emulsion and particularly to a silver halide photol e f I I I I eabove described ob ect IS attained by incorporatgraphic emulsion having fine particles the sensitivity of in a I I I I I I I I g at least one aminostyryl. base represented by the which, with respect to an electron beam, in the case of f H vi l f II t th h t I I irradiation with an electron beam, is remarkably ele- 9 a -h e p opgrdp 1C emu I I I slon containing fine grams of silver halide. vated by sensitizing the emulsion with an aminostyryl G base which is known as a sensitizin d eneml Formula g y 2. Description of the Prior Art In the art of producing'silver halide photographic I emulsions, it is well-known to add a certain kind of 1 sensitizing dye to a silver halide emulsion to thereby 29 N expand its light-sensitive wavelength region.

Furthermore, it has been found that when spectral (L=L)n 2 sensitization is applied to a silver halide emulsion of fine particles by employing a certain sensitizing dye, its region of light sensitive wavelength is not only ex-' 35 I panded, but also the light sensitivity in the region of I I I I intrinsic absorption wavelength of the silver halide is Where"! Z 15 an atomic group Tequlred for formmg a remarkably elevated (US. Pat. No. 3,706,570). heterocyclic ring (which y be Substituted); 1 and In light-sensitive materials for high density recording, 2 are lower alkyls (for example, methyl, ethyL P particularly light-sensitive materials for recording an 30 L is methine hydrogen atom the mfethme electr n beam it required to btain an of a may be substituted nitrile OI the and I'] IS I OI' high image quality and accordingly, first of all, it is required that the particle size of the silver halide be as DESCRIPTION OF THE PREFERRED small possible in order to obtain an image of a high EMBODIMENTS resolving power. However, the reduction of the particle size of the silver halide generally effects the reduction AS the above described hetemcycllc ring there f i i i to h electron b for example, pyridines, oxazoles, benzoxazoles, naph- N i i i m h h f j' Charge f a thoxazoles, benzimidazoles, naphthoimidazoles, thialight-sensitive element at the time of irradiating the" 20 6 benzthiazoles. ph h hiaz l l n zole electron beam be made to decrease in order to repre- 49 benzselenazoles, naphthoselenazoles, and the like. sent a clear image. For this reason, a light-sensitive The aminostyryl bases employed for this invention element having a high sensitivity to electron beams is can be easily synthesized by those skilled in the art by required so that the intensity of the electron beam to be referring to the specifications of, e.g., US. Pat. No. irradiated can be decreased. 2,169,434 and US. Pat. No. 2,345,094, and a publica- For the above-mentioned reasons, for the production tion entitled The Cyanine Dyes and Related Comof light-sensitive elements for recording electron pounds authored by Frances M. Hamer and published beams, a silver halide emulsion having a high electron by John Wiley and Sons Ltd. (1964). beam sensitivity and small a particle'size of the silver In the following, typical aminostyryl bases which may halide as is possible is required, and accordingly, a be employed in the present invention will be illustrated, sensitizing technique with respect to electron beams 50 but it is to be noted that the aminostyryl bases are not becomes a serious problem. limited to them.

Dye I SUMMARY OF THE INVENTION An object of the present invention. therefore. is to provide a silver halide photographic emulsion having a high electron beam sensitivity and which gives a high Dye 2 z s GHQ-1v Dye 14 The silver halide emulsion employed for the present invention contains gelatin or other synthetic polymers as a binder and a silver halide such as silver chloride, silver bromide, silver chlorobromide, silver iodobromide, and silver chloroiodobromide (particularly, silver bromide or silver iodobromide emulsions), said silver halide preferably having a mean grain size, by number or by weight. of no more than 0.2 ,u, particularly no more than 0.1 ,u..

In order to prepare this silver halide photographic emulsion in accordance with the present invention, the dye of the present inventionmay be added to a silver halide emulsion prepared by an ordinary process and on the other hand. a silver halide photographic emulsion having similar advantageous effects as mentioned above can also be obtained by adding the dye to the emulsion in the production process, physical ripening process. or chemical ripening process of the silver halide crystal. The silver halide emulsion of the pres; nt invention may be sensitized with a sulfur compound and gold complex salt or not sensitized therewith. or the emulsion may be spectrally sensitized with a sensitizing dye such as a cyanine and a merocyanine. Furthermore, in accordance with a common method, the silver halide photographic emulsion of the presentinvention may be used in combination with chemical sensitizing agents. stabilizing agents. antifogging agents. matting agents, antistatic agents, hardening agents. surface active agents. plasticizers, or development accelerators etc. and. if required, color formers, fluorescent brightening agents, or color toning agents, etc.

It is usual that the aminostyryl base employed in the present invention is used in the form of a suitable solution which is prepared by dissolving the aminostyryl base into a suitable solvent such as methanol, ethanol, or the like, and the quantity to be added thereof can be varied within a wide range of mg 500 mg per 1 Kg of the emulsion in accordance with desired effects or advantages.

The present invention will be more specifically described by the following illustrative examples.

EXAMPLES A silver bromide emulsion having a mean grain size, by number, of 0.08 t was prepared by a concurrent mixing method, and sulfur sensitization and gold sensi-' tization were applied thereto. Then, the sensitized emulsion was divided into two parts. and the aminostyryl base of the present invention was added to one emulsion and was not added to the other. Each of the resulting emulsions was applied onto a film base of cellulose triacetate to prepare specimens, respectively.

These specimens were subjected to irradiation in a stepwise manner by the use of an electron beam irradiating apparatus under conditions such that the acceleration voltage was 20 KV and the beam current density was within a range of from 10 to l0" coulomb/cm'-. respectively. Then, the irradiated specimens were subjected to development by the use of D-76 developer at a temperature of 20C for 4 minutes, and each characteristic curve of the specimens was obtained.

Assuming that the sensitivity of the'emulsion without the aminostyryl base is l at the point where the optical density is fog +0.5, the common logarithms of the sensitivity of the emulsions to which each suitable quantity of the aminostyryl base was added, that is A log E, are shown in the following Table l as the sensitizing factors of these compounds, respectively.

Table 1 Results of Electron Beam Sensitomctry Quantity Added Sensitization Ex. gr. mol/Kg Factor (Alog E) Nov Dye No. Emulsion at Fog 0.5 Fog Without Addition 0 0 0.03 l l 4 X [0 0.48 0.05 2 2 4 X l0 0.40 0.04 3 3 4 X l0 0.38 0.04 4 4 4 X l0 0.46 0.03 5 5 4 X H) I 0.43 0.03 6 (i 4 X 10 l 0.30 0.03 7 7 4 X 10 l 0.36 0.03 8 8 4 X 10 l 0.40 0.04 9 4 X 10 0.34 0.03 l0 l0 4 X l0 0.35 0.04 ll ll 4 X H] 0.36 0.03 l2 l2 4 X [0 0.30 0.04 [3 l3 4X l0 0.30 004 l4 l4 4 X l0 0.30 0.06

What is claimed is:

1. An electron beam recording process comprising irradiating. with an electron beam. an electron beam recording material comprising a silver halide emulsion whose silver halide grains have a mean grain size no 'jmore than 0.2 micron and have adsorbed thereon at least one aminostyryl base represented by the following formula:

wherein Z is an atomic group required for forming a pyridine, oxazole, benzoxazole, naphthoxazole, benzimidazole, naphthiomidazole, thiazole, benzthiazole, naphthothiazole, selenazole, benzselenazole, or naphthoselenazole ring, R, and R are lower alkyl groups, L

Dze 1 Dxe Z is a methine group, and n is l or 2. and developing the irradiated material to form an image.

2. The process according to claim 1, wherein said silver halide has a mean grain size of no more than 0.]

3. The process according to claim 1, wherein the silver halide is silver bromide or silver iodobromide.

4. The process according to claim 1, wherein the quantity of the aminostyryl base is within the range of 5 mg to 500 mg per 1 Kg of the emulsion 5. The process according to claim 1, wherein said aminostyryl base is selected fromthe group consisting of:

CH f CH N 6. The process according to claim I, irradiating is conducted under ambient 

1. AN ELECTRON BEAM RECORDING PROCESS COMPRISING IRRADIATING, WITH AN ELECTRON BEAM, AN ELECTRON BEAM RECORDING MATERIAL COMPRISING A SILVER HALIDE EMULSION WHOSE SILVER HALIDE GRAINS HAVE A MEAN GRAIN SIZE NO MORE THAN 0.2 MICRON AND HAVE ADSORBED THEREON AT LEAST ONE AMINOSTYRYL BASE REPRESENTED BY THE FOLLOWING FORMULA:
 2. The process according to claim 1, wherein said silver halide has a mean grain size of no more than 0.1 Mu .
 3. The process according to claim 1, wherein the silver halide is silver bromide or silver iodobromide.
 4. The process according to claim 1, wherein the quantity of the aminostyryl base is within the range of 5 mg to 500 mg per 1 Kg of the emulsion.
 5. The process according to claim 1, wherein said aminostyryl base is selected from the group consisting of:
 6. The process according to claim 1, wherein the irradiating is conducted under ambient temperature conditions. 